Constraining the transport coefficient in cold nuclear matter with the Drell-Yan process

By means of the Salgado-Wiedemann (SW) quenching weights and the analytic parametrizations of quenching weights based on the Baier-Dokshitzer-Mueller-Peigné-Schiff (BDMPS) formalism, the leading-order computations for nuclear Drell-Yan differential cross section ratios as a function of the quark momentum fraction are performed with the nuclear geometry effect in Drell-Yan dimuon production and the HKM nuclear parton distribution functions, avoiding overestimation of the nuclear modification in the sea quark distribution. By a global analysis of the Drell-Yan experimental data from NA3 and E866 Collaborations, the extracted transport coefficient with the SW quenching weights is $\widehat{q}=0.32\pm 0.04{\mathrm{GeV}}^2/\mathrm{fm}$, which is approximately equal to the value $\widehat{q}=0.37\pm 0.05{\mathrm{GeV}}^2/\mathrm{fm}$ determined with the analytic parametrizations of BDMPS quenching weights. It is found that the theoretical results are in good agrement with the experimental measurements, and especially the agreement of calculations with NA3 experimental data has a significant improvement. We have also given the predictions for the forthcoming Sea Quest experiment. It is hoped that the obtained value of the transport coefficient in cold nuclear matter can provide a useful reference for determining the precise values of the transport properties of the quark-gluon plasma.

Figure 1

The Drell-Yan cross section ratio $R_{\text{H/Pt}}$ obtained by means of HKM (solid lines), HKN07 (dashed lines), EPS09 (dotted lines), and nDS (dash-dotted lines) without the quark energy loss effect. The experimental data are taken from the NA3 Collaboration [1].

Figure 2

The nuclear Drell-Yan cross section ratios $R_{\text{H/Pt}}\left(x_{1\left(2\right)}\right)$. The solid lines denote the results calculated with SW quenching weights [21] and HKM nuclear parton distributions, and the dashed lines denote the calculations without quark energy loss and without the nuclear parton distribution corrections. The experimental data are taken from the NA3 Collaboration [1].

Figure 3

The nuclear Drell-Yan cross section ratios $R_{\text{W/Be}}\left(x_1\right)$ calculated with SW quenching weights [21] and HKM nuclear parton distributions. The experimental data are taken from the E866 Collaboration [4].

Figure 4

The nuclear Drell-Yan cross section ratios $R_{\text{Fe/Be}}\left(x_1\right)$ calculated with SW quenching weights [21]and HKM nuclear parton distributions. The experimental data are taken from the E866 Collaboration [4].

Figure 5

The nuclear Drell-Yan cross section ratios $R_{A/\text{Be}}\left(x_2\right)$ calculated with SW quenching weights [21] and HKM nuclear parton distributions. The experimental data are taken from the E866 Collaboration [4].

Figure 6

The nuclear Drell-Yan cross section ratios $R_{A/\text{D}}\left(x_{1,\left(2\right)}\right)$ for the forthcoming E906 Sea Quest experiment calculated with SW quenching weights [21] and the HKM nuclear parton distributions. The solid lines correspond to $R_{\text{Fe/D}}\left(x_{1,\left(2\right)}\right)$ and the dashed lines correspond to $R_{\text{W/D}}\left(x_{1,\left(2\right)}\right)$